Reproduction apparatus

ABSTRACT

There is provided a reproduction apparatus for reproducing stream data recorded on a recording medium, the stream data containing menu item coordinate information representing a display location of a menu item and image information representing an image. The reproduction apparatus includes: a reading section for reading the stream data from the recording medium; an extraction section for extracting the menu item coordinate information contained in the stream data; a reproduction section for reproducing the image information contained in the stream data; a determination section for determining whether or not the menu item has been selected by comparing the extracted menu item coordinate information against a user input in the form of coordinate information; and an execution section for executing a process corresponding to the menu item if the menu item is determined to have been selected.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a reproduction apparatus forselectively outputting an image signal from a recording medium on whichdigital data representing image information is recorded.

[0003] 2. Description of the Related Art

[0004] Due to recent development in technologies, optical disks havingan information capacity eight times that of a video CD have beendeveloped, and consequently optical disk reproduction apparatuses areattracting attention as new AV (audio-visual) apparatuses. As a result,studies have been conducted on applications of optical disks forallowing a user to select a predetermined image, out of multiple hoursof image information, in an interactive manner.

[0005] Hereinafter, a method for selecting a predetermined image from aplurality of images by using a menu will be described.

[0006]FIG. 5 schematically illustrates an exemplary conventional opticaldisk reproduction system. The optical disk reproduction system includesan optical disk reproduction apparatus 51 and a display 52 such as atelevision set.

[0007] The optical disk reproduction apparatus 51 is controlled by meansof a remote controller 53. The optical disk reproduction apparatus 51reproduces image information recorded on an optical disk (not shown) andthe display 52 displays the reproduced image information.

[0008] Menu information for allowing the selection of one of a pluralityof items is recorded on the optical disk. As the optical diskreproduction apparatus 51 reproduces the menu information, a menu isdisplayed on the display 52. The user selects one of the items containedin the menu by using the remote controller 53. For example, in the casewhere the menu exhibits a set of numbers correspondingly indicating therespective items, the user may press a key on the remote controller 53that has the same number as the number of one of the indicated items toselect the desired item from among the plurality of items in the menu.Alternatively, the user may press up/down/right/left keys on the remotecontroller 53 to cause a corresponding movement of a highlighted regionwhich is displayed over the menu, and then press a decision key on theremote controller 53 to select the highlighted item from the items inthe menu.

[0009] Next, a method for selecting one of a plurality of so-called“angles” (e.g., images respectively corresponding to differentperspectives of the same scene or images respectively corresponding todifferent scenes) will be described. Such a plurality of “angles” areinterleaved on the optical disk on which they are recorded, withdifferent numbers being assigned to different “angles”. When the opticaldisk reproduction apparatus 51 reproduces the data which is recorded inthis manner, the motion pictures from only one “angle” are reproduced.During the reproduction of the motion pictures from that “angle”, theuser can press a number key on the remote controller to select another“angle” corresponding to that number, whereby the motion pictures fromthat “angle” will begin to be reproduced.

[0010] However, the above-described prior technique of selecting one ofa plurality of items contained in a menu by pressing a number key of aremote controller is not very interactive. Similarly, theabove-described prior technique of selecting one of a plurality of“angles” during the reproduction of the motion pictures from only one“angle” is not very interactive because the user needs to know inadvance when it is possible to select from a plurality of “angles”,i.e., when such “angles” are available. Therefore, a function forallowing an effective selection of menu items or “angles” is desired.

SUMMARY OF THE INVENTION

[0011] According to the present invention, there is provided areproduction apparatus for reproducing stream data recorded on arecording medium, the stream data containing menu item coordinateinformation representing a display location of a menu item and imageinformation representing an image. The reproduction apparatus includes:a reading section for reading the stream data from the recording medium;an extraction section for extracting the menu item coordinateinformation contained in the stream data; a reproduction section forreproducing the image information contained in the stream data; adetermination section for determining whether or not the menu item hasbeen selected by comparing the extracted menu item coordinateinformation against a user input in the form of coordinate information;and an execution section for executing a process corresponding to themenu item if the menu item is determined to have been selected.

[0012] In one embodiment of the invention, the user input is supplied tothe reproduction apparatus via a touch panel.

[0013] In another embodiment of the invention, the user input issupplied to the reproduction apparatus via a mouse.

[0014] In another aspect of the invention, there is provided areproduction apparatus for reproducing stream data recorded on arecording medium, the stream data containing a plurality of selectableimage information units. The reproduction apparatus includes: a readingsection for reading the stream data from the recording medium; areproduction section for reproducing the stream data; a detectionsection for detecting a period during which the plurality of selectableimage information units contained in the stream data are reproducible;an image display section for displaying images respectively representingthe plurality of selectable image information units during the period; adetermination section for determining which one of the imagesrepresenting the plurality of selectable image information units hasbeen selected by comparing coordinate information fed as a user inputvia a pointing device and display location information representingdisplay locations of the images; and a control section for executing aprocess for displaying one of the images that has been determined asselected while not displaying the other images.

[0015] In one embodiment of the invention, the pointing device is amouse.

[0016] Thus, the invention described herein makes possible theadvantages of providing a reproduction apparatus which allows theselection of desired image information in an interactive manner, bydirectly pointing to a menu item or an “angle” on the display with apointing device, e.g., a touch panel.

[0017] This and other advantages of the present invention will becomeapparent to those skilled in the art upon reading and understanding thefollowing detailed description with reference to the accompanyingfigures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a view illustrating an optical disk reproduction system1 according to the present invention.

[0019]FIG. 2 is a diagram illustrating the data structure of data whichis recorded on an optical disk 21 according to Example 1 of the presentinvention.

[0020]FIG. 3 is a block diagram illustrating the structure of an opticaldisk reproduction apparatus 11 according to Example 1 of the presentinvention.

[0021]FIG. 4 is a diagram illustrating menu items available duringreproduction according to Example 1 of the present invention.

[0022]FIG. 5 is a view illustrating a conventional optical diskreproduction apparatus.

[0023]FIG. 6 is a diagram illustrating the data structure of datarecorded on an optical disk 611 according to Example 2 of the presentinvention.

[0024]FIG. 7 is a block diagram illustrating the structure of an opticaldisk reproduction apparatus 70 according to Example 2 of the presentinvention.

[0025]FIG. 8 is a diagram illustrating exemplary reproduced image dataaccording to Example 2 of the present invention.

[0026]FIG. 9 is a view illustrating the structure of an optical diskreproduction system 9 according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLE 1

[0027] Hereinafter, the present invention will be described by way ofexamples, with reference to the accompanying figures.

[0028]FIG. 1 illustrates an optical disk reproduction system 1 accordingto the present invention.

[0029] The optical disk reproduction system 1 includes: an optical diskreproduction apparatus 11 for reproducing image information and/or audioinformation recorded on an optical disk (not shown); a display 12, e.g.,a television set, for outputting image information and/or audioinformation reproduced by the optical disk reproduction apparatus 11;and a touch panel 13 overlaid on the screen of the display 12. The touchpanel 13 functions as a position detection device for detecting aposition in the displayed image on the display 12. The positioninformation which has been detected by the touch panel 13 is input tothe optical disk reproduction apparatus 11.

[0030]FIG. 2 illustrates the data structure of MPEG2 stream data 22recorded on an optical disk 21. The MPEG2 stream data 22 is reproducedby the optical disk reproduction apparatus 11 shown in FIG. 1.

[0031] The MPEG2 stream data 22 includes at least a private stream 221and image information 222. The private stream 221 includes highlightdata 221 a and valid duration information 221 b. The highlight data 221a is inserted in the MPEG2 stream data 22 at predetermined time periods.The valid duration information 221 b represents the duration for whichthe control information in the highlight data 221 a is valid. The validduration of the highlight data 221 a is, by default, the period of timebetween the time when the highlight data is processed and the time whenthe next highlight data is processed.

[0032] The highlight data 221 a includes selection item information 221a-1 to 221 a-n (where n is an integer equal to or greater than 1). Theselection item information contains information concerning an item(hereinafter referred to as “selection item”) to be displayed forselection. For example, the selection item information includes data forhighlighting a certain rectangular region on the display image forprompting a user to select a selection item. The selection item can be anumber, a letter, or a motion picture. Each of the selection iteminformation 221 a-1 to 221 a-n at least includes menu item coordinateinformation 221 a-k1 and control information 221 a-k2 (where k is aninteger between 1 and n). The menu item coordinate information 221 a-k1includes coordinates representing the position of a menu item, i.e.,coordinates representing a rectangular region in the display image whichcan be highlighted for prompting a user to select a selection item.

[0033] Although the optical disk 21 is illustrated as a recording mediumin the present specification, any recording medium other than opticaldisks can be suitably employed.

[0034]FIG. 3 illustrates the structure of an optical disk reproductionapparatus 11.

[0035] The optical disk reproduction apparatus 11 includes a datareading section 31, an MPEG2 stream data reproduction section 32, aprivate stream acquisition section 33, a control information processingsection 34, a position comparison section 35, and a position detectionsection 36.

[0036] The data reading section 31 reads the MPEG2 stream data 22recorded on the optical disk 21, and outputs the MPEG2 stream data 22which has been read to the MPEG2 stream data reproduction section 32. Inaddition, the data reading section 31 extracts the private stream 221contained in the MPEG2 stream data 22 which has been read, and outputsthe extracted private stream 221 to the private stream acquisitionsection 33.

[0037] The MPEG2 stream data reproduction section 32 receives the MPEG2stream data 22 from the data reading section 31, and reproduces thereceived MPEG2 stream data 22. The MPEG2 stream data reproductionsection 32 outputs the reproduced MPEG2 stream data 22 to the display 12(FIG. 1). The display 12 (FIG. 1) displays the reproduced MPEG2 streamdata 22. By reproducing the image information 222 (FIG. 2) contained inthe MPEG2 stream data 22, an image is displayed on the display 12. Byreproducing the selection item information 221 a-k (FIG. 2), a menu itemis displayed on the display 12.

[0038] The private stream acquisition section 33 obtains the privatestream 221 from the data reading section 31 and extracts the menu itemcoordinate information 221 a-k1 and control information 221 a-k2, aswell as the valid duration information 221 b (FIG. 2) from the acquiredprivate stream 221.

[0039] The extraction of the menu item coordinate information 221 a-k1is achieved by analyzing the highlight data 221 a contained in the MPEG2stream data 22 at a highlight data analysis section 331. The extractionof the control information 221 a-k2 and the valid duration information221 b is performed by a control information acquisition section 332.

[0040] The extracted menu item coordinate information 221 a-k1 is outputto the position comparison section 35. The extracted control information221 a-k2 and the valid duration information 221 b are output to thecontrol information processing section 34.

[0041] The position detection section 36 detects the position which auser has input via the touch panel 13. The information of the detectedposition is converted into coordinate information representingcoordinates on the plane of the display and output to the positioncomparison section 35.

[0042] The position comparison section 35 compares the coordinateinformation detected by the position detection section 36 and the menuitem coordinate information 221 a-k1 received from the highlight dataanalysis section 331, to determine whether or not the position indicatedby the detected coordinate information is within a rectangular regionspecified by the menu item coordinate information. Based on thedetermination result, the position comparison section 35 outputs controlinformation (corresponding to the region which has been determined tocontain the position indicated by the detected coordinate information)to the control information processing section 34.

[0043] The operation of the position comparison section 35 will bedescribed later in more detail with reference to FIG. 4.

[0044] If the position comparison section 35 determines that theposition indicated by the input coordinate information is within therectangular region specified by the menu item coordinate information,the position comparison section 35 assumes that the selection item hasbeen pointed to and outputs a control signal to the control informationprocessing section 34 instructing that the rectangular highlightedregion should be moved to the position at which the selection item isdisplayed. Having received the control signal, the control informationprocessing section 34 controls the display so that the rectangularhighlighted region is moved accordingly. If a position within therectangular highlighted region (representing a selection item) isdetermined to have been pointed to for a predetermined period of time orlonger, the position comparison section 35 determines that the selectionitem has been selected. The position comparison section 35 outputscontrol information corresponding to the selection item to the controlinformation processing section 34. Based on the input controlinformation, the control information processing section 34 controls thedata reading section 31 so as to reproduce motion picture informationwhich has been selected.

[0045] The control information processing section 34 receives thecontrol information 221 a-k2 and the valid duration information 221 bfrom the control information acquisition section 332 (included in theprivate stream acquisition section 33), as well as the controlinformation from the position comparison section 35, so as to controlthe data reading section 31 based on the received information. Under thecontrol of the control information processing section 34, the datareading section 31 reads the necessary MPEG2 stream data.

[0046]FIG. 4 illustrates an exemplary image displayed on the display 12,with three selection items (i.e., menu items 1 to 3) being displayed byreproducing the MPEG2 stream data. Although not shown in FIG. 4, a touchpanel 13 (FIG. 1) is provided so as to overlay the screen of the display12.

[0047] The menu item 1 is a rectangular region defined by two diagonalpositions respectively having the coordinates (X₁, Y₁) and (X₁′, Y₁′).The coordinates (X₁, Y₁) and (X₁′, Y₁′) are represented by, for example,the menu item coordinate information 221 a-11 contained in the selectionitem information 221 a-1 shown in FIG. 2.

[0048] The menu item 2 is a rectangular region defined by two diagonalpositions respectively having the coordinates (X₂, Y₂) and (X₂′, Y₂′).The coordinates (X₂, Y₂) and (X₂′, Y₂′) are represented by, for example,the menu item coordinate information 221 a-21 contained in the selectionitem information 221 a-2 shown in FIG. 2.

[0049] The menu item 3 is a rectangular region defined by two diagonalpositions respectively having the coordinates (X₃, Y₃) and (X₃′, Y₃′).The coordinates (X₃, Y₃) and (X₃′, Y₃′) are represented by, for example,the menu item coordinate information 221 a-31 contained in the selectionitem information 221 a-3 shown in FIG. 2.

[0050] Although the positions of the menu items are denoted bycoordinates in the present example, any other denotation method can beemployed as long as the positions of the menu items can be specified.Although the menu items are illustrated as rectangular regions in thepresent example, the shapes of the menu items are not limited torectangles.

[0051] Now, the method of determination by the position comparisonsection 35 (FIG. 3) as to whether or not a menu item has been selectedwill be described in more detail.

[0052] The determination as to whether the menu 1 in FIG. 4 has beenselected can be made in accordance with eq. 1 below:

X_(n)>X₁ and X_(n)<X₁′

Y_(n)>Y₁ and Y_(n)<Y₁′  eq. 1

[0053] Herein, (X₁, Y₁) and (X₁′, Y₁′) represent the coordinates of theupper left apex and the lower right apex, respectively, of therectangular region specified by the menu item coordinate information.The coordinates (X_(n), Y_(n)) represent the coordinate informationwhich has been detected by the position detection section 36 (FIG. 3).

[0054] If eq. 1 is satisfied, the menu item 1 is determined to have beenpointed to because the input position is within the rectangular regionspecified by the menu item coordinate information.

[0055] If the menu item 1 is determined to have been selected (i.e.,after the menu item 1 is determined to have been pointed to for apredetermined period of time or longer), the control informationcorresponding to the menu item 1 is output to the control informationprocessing section 34. Based on the input control information, thecontrol information processing section 34 highlights a rectangularregion corresponding to the menu item 1 and controls the data readingsection 31 so as to reproduce the motion pictures corresponding to themenu item 1.

[0056] If eq. 1 is not satisfied, the menu item 1 is not determined tohave been selected because the input position is outside the rectangularregion specified by the menu item coordinate information.

[0057] Thus, the user can easily select one of a plurality of visualizedmenu items as described above. Therefore, the menu items do not need tobe denoted with numbers and/or letters; the menu items can be, e.g.,motion pictures.

[0058] As described above, in accordance with the optical diskreproduction apparatus according to Example 1 of the present invention,it is possible to control the optical disk reproduction apparatus byselecting a menu item by merely pointing to a menu item on the displayso that the control information associated therewith is executed.

[0059] Although MPEG2 stream data is illustrated as the data recorded onthe optical disk in the present example, the data is not limited theretobut can also be other types of motion picture stream data.

[0060] Although a touch panel is illustrated as the detection device fordetecting a position on the display, any other means for detecting aposition can alternatively be used. In the case where the optical diskreproduction apparatus according to the present invention is coupled toa computer,, a pointing device, e.g., a mouse, or a pen tablet, can beutilized as the detection device for detecting a position on thedisplay.

[0061] In the case where the displayed image on a computer display isenlarged or reduced, it is still possible to properly determine whichposition in the displayed image is pointed to because the computer cankeep track of the original size of the image under reproduction in sucha manner that it can calculate which position in the original image isbeing pointed to relative to the position which is input on the actuallydisplayed image. The calculation result can be output to the opticaldisk reproduction apparatus as relative position information.

EXAMPLE 2

[0062] Hereinafter, a second example of the present invention will bedescribed with reference to FIGS. 6, 7, 8, and 9.

[0063]FIG. 9 illustrates the structure of an optical disk reproductionsystem 9 according to the present invention.

[0064] The optical disk reproduction system 9 includes a computer 92, adisplay 93, and a mouse 94 as a detection device for detecting aposition in an image which is displayed on the display 93. The computer92 includes an optical disk reproduction apparatus 70 internalizedtherein.

[0065] The display 93, which is coupled to the computer 92, receivesimage output data from the computer 92 so as to display images. Themouse 94 is coupled to the computer 92 as a position input device. Theoptical disk reproduction apparatus 70 reproduces image and/or audioinformation recorded on an optical disk (not shown). The optical diskreproduction apparatus 70 receives the input from the mouse 94 via thecomputer 92, and outputs an image signal and/or an audio signal to thedisplay 93 and/or loudspeakers (not shown).

[0066] Although the optical disk reproduction apparatus 70 is describedto be internalized in the computer 92 in the present example, theoptical disk reproduction apparatus 70 can alternatively be providedexternally to the computer 92.

[0067] Alternatively, the computer 92 may perform some of the functionsof the optical disk reproduction apparatus 70; for example, the computer92 can reproduce the information recorded on an optical disk.

[0068] Although an optical disk is illustrated as a recording medium inthe present specification, any recording medium other than optical diskscan be suitably employed.

[0069]FIG. 6 illustrates the structure of MPEG2 stream data 612 recordedon an optical disk 611. The MPEG2 stream data 612 is to be reproduced bythe optical disk reproduction apparatus 70 (FIG. 9).

[0070] The MPEG2 stream data 612 includes management information 628 a,628 b, and 628 c, image information 630, and audio information 631. Themanagement information 628 a, 628 b, and 628 c are recorded, atpredetermined time periods, in the MPEG2 stream data 612. The imageinformation 630 represents information concerning images, whereas theaudio information 631 represents information concerning sounds.

[0071] The MPEG2 stream data 612 includes a multi-angle data structure.Herein, a “multi-angle data structure” is defined as a structureincluding a plurality of image data 630 and/or audio data 631corresponding to different “angles” (as defined above) such that theimage data 630 and/or audio data 631 are divided into interleavedblocks. For example, the multi-angle data structure may be a structureincluding block 1 of angle 1 (624), block 1 of angle 2 (625), . . . ,block n of angle 1 (626), and block n of angle 2 (627).

[0072] The period of time during which the MPEG2 stream data 612 isreproduced is divided into an angle reproduction period 622 (i.e., aperiod of time during which information contained in the multi-angledata structure is reproduced) and regular reproduction periods 623 a and623 b (i.e., periods of time during which information other than thatcontained in the multi-angle data structure is reproduced).

[0073] During the reproduction of the MPEG2 stream data 612, the anglereproduction period 622 is detected based on the management information.For each given period, the management information includes informationindicating the presence/absence of an angle period and the recordedposition of each angle block. By detecting the angle reproduction period622, it becomes possible to reproduce and display images viewed from aplurality of “angles” on the same displayed image, as described later inmore detail.

[0074]FIG. 7 illustrates the structure of the optical disk reproductionapparatus 70.

[0075] The optical disk reproduction apparatus 70 includes a datareading section 71, an MPEG2 stream data reproduction section 72, acontrol section 73, a storage size/position change section 74, an imagedata output section 75, and an image data storage section 76.

[0076] The data reading section 71 reads the MPEG2 stream data 612recorded on the optical disk 611. The data reading section 71 storespredetermined units of the MPEG2 stream data 612 which has been read inan internal memory buffer (not shown). The data reading section 71outputs the MPEG2 stream data 612 which is stored in an internal memorybuffer to the control section 73. The data reading section 71 receivesthe result of determination of the kind of data contained in the MPEG2stream data 612 from the control section 73. Based on the receiveddetermination result from the control section 73, the data readingsection 71 outputs the image information 630 and the audio information631 contained in the MPEG2 stream data 612 to the MPEG2 stream datareproduction section 72, and stores the management information 628 a to628 c in the memory buffer. Furthermore, the data reading section 71receives control information from the control section 73 indicatingwhich angle block should be read out, and reads only the blocks of theselected “angle” from the optical disk 611.

[0077] The MPEG2 stream data reproduction section 72 receives the imageinformation 630 and the audio information 631 from the data readingsection 71. The MPEG2 stream data reproduction section 72 separates thereceived image information 630 from the audio information 631, andreproduces the image information 630 and the audio information 631 bysubjecting them to conversion processes as necessary. The MPEG2 streamdata reproduction section 72 outputs the reproduced image information630 (as image data 6301) to the storage size/position change section 74,and the reproduced audio information 631 (as audio output data 631′) tothe exterior of the optical disk reproduction apparatus 70.

[0078] The control section 73 receives the MPEG2 stream data 612 fromthe data reading section 71. An analysis section 731 analyzes the MPEG2stream data 612 in order to determine whether the analyzed data is theimage information 630, the audio information 631, or the managementinformation 628 a to 628 c, following a method according to the MPEG2specification. The control section 73 outputs the determination resultto the data reading section 71.

[0079] If an angle reproduction period 622 (FIG. 6) is reached duringthe reproduction of the MPEG2 stream data 612, the analysis section 731of the control section 73 detects that the currently-reproduced periodis an angle reproduction period, based on the determination of themanagement information stored in the internal memory buffer. If thecurrently-reproduced period is thus determined as an angle reproductionperiod, the analysis section 731 further analyzes the managementinformation 628 a to 628 c stored in the internal memory buffer. Thecalculation section 732 calculates the number of subsections (i.e.,angles) into which the displayed image is to be divided (in accordancewith the number of interleaved “angles”), as well as the reduction ratefor each “angle” image. For example, if the number of “angles” is four,then the displayed image is to be divided into four subsections,requiring a reduction rate of ¼. Once the number of subsections of thedisplayed image and the reduction rate are thus determined, the controlsection 73 outputs a stored information signal 735 (containing thenumber of subsections of the displayed image and the reduction rate) tothe storage size/position change section 74. The output of the storedinformation signal 735 is made based on the angle number of the angleblock under reproduction.

[0080] The position information indicating a position on the displaypointed to by the user with a mouse is detected by the positiondetection section 77 and the detected position information is convertedinto coordinate information representing coordinates on the plane of thedisplay and output to the position comparison section 733. The positioncomparison section 733 determines which “angle” is being displayed atthe position indicated by the position information which has beendetected by the position detection section 77. As a result of thedetermination, the control section 73 controls the data reading section71 so as to read only the angle block which is displayed at the positionindicated by the position information.

[0081] The storage size/position change section 74 receives from theMPEG2 stream data reproduction section 72 the image information 630 (asimage data 630′) that has been subjected to necessary conversionprocesses, and receives the stored information signal 735 from thecontrol section 73. Based on the reduction rate contained in the storedinformation signal 735, the storage size/position change section 74reduces the size of the image data 630′ received from the MPEG2 streamreproduction section 72. Furthermore, based on the number of subsectionsof the displayed image and the angle number contained in the storedinformation signal 735, the storage size/position change section 74determines which position (hereinafter referred to as the “storageposition”) on the display the image data 630′ is to be displayed, priorto storage in the image data storage section 76. The image data 630′ isstored angle by angle. The storage position is preferably determined soas not to overlap with the displayed image of the image data 630′ thathas been previously stored; alternatively, the storage position mayoverlap with the displayed image of the previously-stored image data630′.

[0082] After the size of the image data 630′ is reduced and its storageposition is determined, the storage size/position change section 74outputs the image data 630′ to the image data storage section 76.

[0083] The image data storage section 76 receives the image data 630′from the storage size/position change section 74 and stores the receivedimage data 630′. The image data storage section 76 outputs the receivedimage data 630′ to the image data output section 75.

[0084] Upon receiving the image data 630′ from the image data storagesection 76, the image data output section 75 converts the image data630′ into, for example, a signal conforming to the NTSC (NationalTelevision System Committee) standard (number of scanning lines: 525;frame frequency: 30 Hz; image signal band: 4.2 MHz; horizontalsynchronization frequency: 15.750 kHz), which is output to the exteriorof the optical disk reproduction apparatus 70.

[0085] For example, in the aforementioned case where the number ofsubsections of the displayed image is four, the respective image data ofthe subsections are stored for output at the positions shown in FIG. 8.In FIG. 8, the image data corresponding to angle number 1 is denoted asimage data 1; the image data corresponding to angle number 2 is denotedas image data 2; the image data corresponding to angle number 3 isdenoted as image data 3; and the image data corresponding to anglenumber 4 is denoted as image data 4.

[0086] The image data corresponding to the respective “angles” aredisplayed to be utilized as index images for the respective “angles”.Herein, an “index image” is defined as an image representing the imageinformation contained in each angle block. When the storage of theinterleaved image data corresponding to all the “angles” (i.e., fourangles in this exemplary case) is complete, the index images are updatedin accordance with the image data of “angles” which will be read in thesubsequent cycle of “angles”. When updating the index images, the imagedata output section 75 reads and outputs the image data of all storageregions in the image data storage section 76. As a result, the user canvisually recognize that the angle reproduction period 622 in the MPEG2stream data 612 is being reproduced, and further visually recognizewhich “angles” are available in this angle reproduction period 622.

[0087] During the above-described index image displaying process, theuser can determine the “angle” which the user desires to reproduce anddesignate a position where that “angle” is being displayed by using themouse 94 (FIG. 9). Upon the designation made by the user, the controlsection 73 terminates the index image displaying process and controlsthe data reading section 71 so as to read only the selected “angle”(similarly to the case of reproducing a single image). Thereafter, theselected “angle” is displayed on the display 93 (FIG. 9).

[0088] The determination as to which “angle” has been selected is madein a position comparison section 733 (FIG. 7) in a similar manner to thedetermination illustrated in Example 1 concerning whether a menu itemhas been selected or not, i.e., based on a coordinate denotation of aposition in the displayed image that has been input by the user via themouse 94 (FIG. 9), and on a coordinate denotation of the positions ofregions displaying the respective “angles” as calculated based on thenumber of subsections of the displayed image and the reduction rate.Thus, it can be determined which “angle” is being displayed at theposition that has been input by the user via the mouse 94.

[0089] Thus, an optical disk reproduction apparatus has been describedwhich allows the selection of desired image information in aninteractive manner, by directly pointing to one of a plurality of“angles” with a mouse coupled to a computer.

[0090] Although the selection of “angles” reproduced in the index imagedisplaying process in the present example is described as being achievedby using a mouse to designate an angle position to be selected, thedevice for designating an angle position is not limited to a mouse.Alternatively, a pointing device such as a touch panel or a pen tabletas described in Example 1 can be used, for example. The user can selectan “angle” in an interactive manner, the selection being known throughcomparison between a position on the display designated with such apointing device and the positions of the index images.

[0091] Alternatively, the selection of the “angle” reproduced in theindex image displaying process can be made by designating the number ofthe desired “angle” with a remote controller or the like.

[0092] In the case where the displayed image on a computer display isenlarged or reduced, it is still possible to properly determine whichposition in the displayed image is pointed to because the computer cankeep track of the original size of the image under reproduction in sucha manner that it can calculate which position in the original image isbeing pointed to relative to the position which is input on the actuallydisplayed image. The calculation result can be output to the opticaldisk reproduction apparatus as relative position information.

[0093] Although the present example employs a MPEG2 stream (referred toas a program stream) in such a manner that a motion picture elementarystream is divided into “angles” during an angle reproduction period, itis also applicable to employ a so-called transport stream, i.e., amultistream composed of a plurality of MPEG streams in such a mannerthat the images of different “angles” are contained in respectivelydifferent streams.

[0094] Although the information for identifying angle reproductionperiods during reproduction of the MPEG2 stream data in the presentexample is described to be contained in the control information, whichis interleaved in the MPEG2 stream data at predetermined periods, theinformation for identification can be contained in a region differentfrom the region in which the MPEG2 stream data is contained. In thiscase, the optical disk reproduction apparatus can begin the reproductionof MPEG2 stream data after reading the information for identificationand storing it in an internal memory at the beginning of thereproduction.

[0095] As described above, according to the present invention, the usercan select from menu items or “angles” by directly pointing to a desiredmenu item or “angle” on the display by using a pointing device.

[0096] Since the user selects a menu item by directly designating a menuitem on the display, the menu does not need to contain numbers orletters, thereby providing for more liberty in the creation of contents.

[0097] Furthermore, the user can control the display image by choosingan image on the display without necessarily comprehending, if at all,any numbers or letters.

[0098] In a multiple image mode, all the interleaved “angles” recordedon the optical disk can be reproduced and simultaneously displayed asindex images composing one display image. A user can confirm the contentof the “angles” based on the index images and visually select a desired“angle” without difficulty.

[0099] Various other modifications will be apparent to and can bereadily made by those skilled in the art without departing from thescope and spirit of this invention. Accordingly, it is not intended thatthe scope of the claims appended hereto be limited to the description asset forth herein, but rather that the claims be broadly construed.

What is claimed is:
 1. A reproduction apparatus for reproducing streamdata recorded on a recording medium, the stream data containing menuitem coordinate information representing a display location of a menuitem and image information representing an image, wherein thereproduction apparatus comprises: a reading section for reading thestream data from the recording medium; an extraction section forextracting the menu item coordinate information contained in the streamdata; a reproduction section for reproducing the image informationcontained in the stream data; a determination section for determiningwhether or not the menu item has been selected by comparing theextracted menu item coordinate information against a user input in theform of coordinate information; and an execution section for executing aprocess corresponding to the menu item if the menu item is determined tohave been selected.
 2. A reproduction apparatus according to claim 1 ,wherein the user input is supplied to the reproduction apparatus via atouch panel.
 3. A reproduction apparatus according to claim 1 , whereinthe user input is supplied to the reproduction apparatus via a mouse. 4.A reproduction apparatus for reproducing stream data recorded on arecording medium, the stream data containing a plurality of selectableimage information units, wherein the reproduction apparatus comprises: areading section for reading the stream data from the recording medium; areproduction section for reproducing the stream data; a detectionsection for detecting a period during which the plurality of selectableimage information units contained in the stream data are reproducible;an image display section for displaying images respectively representingthe plurality of selectable image information units during the period; adetermination section for determining which one of the imagesrepresenting the plurality of selectable image information units hasbeen selected by comparing coordinate information fed as a user inputvia a pointing device and display location information representingdisplay locations of the images; and a control section for executing aprocess for displaying one of the images that has been determined asselected while not displaying the other images.
 5. A reproductionapparatus according to claim 4 , wherein the pointing device is a mouse.